The team's new Russian partners are keen for Sirotkin to be on the grid as soon as he is ready, and Sauber is carrying out a development programme with him in older machinery in preparation.
Asked how long the squad could wait before making a call on Sirotkin, Sauber team boss Monisha Kaltenborn played down the likelihood of leaving the decision until the eve of 2014 testing.
"I think we will know pretty soon if we think he can make sense [for a 2014 race seat] or not," she said.
"We know the responsibility we have and the key to getting all this is getting the Superlicence.
"We are confident he can achieve that, but it is a step that you should not underestimate."
Kaltenborn said Sirotkin was making good progress, and that a lot of the required work was down to his own fitness efforts.
"Our target is clearly to get him into F1. He was supposed to have two tests but one couldn't happen because of the weather and the other one was a good test," she said.
"He has some other driving activities, so it is important that he continues to focus on his preparation, on the physical side, and you cannot underestimate that."